In a wafer carrier device, it is necessary that a robot correctly carries a wafer to a predetermined position within a processing unit to prevent failures such as wafer drops and incorrect processings. However, owing to various reasons such as dimensional errors of components composing the device, assembly errors of the device and the like, in actuality, a wafer is not correctly carried to a predetermined position even if the carrier robot is shifted to a position of the design value. Accordingly, a teaching operation of the carrier robot is required prior to operating the carrier device.
In conventional carrier robot teaching methods, without necessitating high-order skills of an operator, for the purpose of swiftly carrying out a teaching operation with a fixed accuracy at all times, a teaching method for a transfer unit of a semiconductor manufacturing apparatus has been described in the Unexamined Japanese Patent Application Publication No. Hei09-102527. Hereinafter, this is briefly described by use of the drawings.
In FIG. 8, reference numeral 14 denotes a jig composed of a circular plate having an identical form and size to that of a wafer and a columnar pin provided in a standing condition at a center position thereof. In FIG. 9, a detecting member 16 is provided at a front surface portion of a transfer unit 15 for carrying a wafer, and this is a detecting member for optically detecting a position of the jig 14. In the above construction, while installing the transfer unit 15 at its home position, an operator detects, by the detecting member 16, the circular plate portion and pin of the jig 14 filled by insertion into a boat 17 and obtains positions in the X-axis direction, Y-axis direction, and Z-axis direction of the jig 14 with reference to the transfer unit 15.
In the teaching method for a transfer unit of a semiconductor manufacturing apparatus as in the above, position data of the transfer unit 15 for filling a wafer by insertion into the boat 17 can be obtained.
However, in recent semiconductor manufacturing apparatuses, with the advancement of high density, operational space of the transfer unit has been narrowed, and it has become difficult to carry out correct teaching of the transfer unit, and in teaching, even teaching jigs cannot be utilized.